The Src homology and collagen A (ShcA) adaptor protein may participate in the pathogenesis of membranous lupus nephritis

The Src homology and collagen A (ShcA) adaptor protein that binds to tyrosine kinase receptors. ShcA plays a role in insulin signaling, stress resistance and energy metabolism. The 66-kDa Src homology 2 domain-containing protein (p66shc) belongs to the ShcA family and has been associated with reactive oxygen species (ROS); increased ROS is involved in the pathology of lupus nephritis (LN). However, whether ShcA can act as a biomarker for oxidative injury in LN is unknown. This study is aimed to investigate the ShcA expression in kidney tissues from patients presenting with LN and the association between ShcA expression and clinical parameters. Renal biopsy tissues were obtained from 62 LN, 20 primary membranous nephropathy (MN) and 10 other secondary MN patients. ShcA was measured by immunofluorescence. The expression of ShcA in the membranous lupus nephritis (class V) group showed a higher trend but there were no significant differences compared with pure mesangial disease (class II) and proliferative (Class III/IV) lupus nephritis. ShcA deposits were negative in primary and other secondary MN. ShcA might act as a new biomarker and a diagnostic tool to identify membranous lupus nephritis with other MN.

[Relationship between UGT1A1 gene polymorphisms and irinotecan-induced severe adverse events]

Objective: To investigate the relationship between UGT1A1*6, UGT1A1*28, UGT1A1*60 and UGT1A1*93 polymorphisms and irinotecan-induced severe adverse reactions(grade 3-4 delayed diarrhea and neutropenia) in Chinese cancer patients. Methods: A total of 141 cancer patients treated with irinotecan were enrolled in this study. Peripheral venous blood was collected and genomic DNA was extracted. The genetic polymorphisms of UGT1A1*6, UGT1A1*28, UGT1A1*60 and UGT1A1*93 were analyzed by PCR and direct sequencing. The adverse reactions during chemotherapy were observed and recorded. The incidence of severe adverse reactions was compared among patients with different genotypes. Results: Among 141 patients, the cases with UGT1A1*6 GG, GA and AA genotypes were 71, 54 and 16, while those with UGT1A1*28 TA6/6, TA6/7 and TA7/7 genotypes were 105, 33 and 3, respectively. The cases with UGT1A1*60 AA, AC and CC genotypes were 52, 80 and 9, while those with UGT1A1*93 GG, GA and AA genotypes were 105, 32 and 4, respectively. The patients with grade 3-4 delayed diarrhea and neutropenia were 23 and 56, respectively. Multivariate logistic regression analysis showed that UGT1A1*6 and UGT1A1*60 genetic polymorphisms were independent factors influencing the occurrence of grade 3-4 delayed diarrhea. The risk of grade 3-4 delayed diarrhea in homozygous AA carriers of UGT1A1*6 increased 3.79 times compared with that in wild-type GG carriers (95%CI: 1.35-10.67). Moreover, the risk of grade 3-4 delayed diarrhea in homozygous CC carriers of UGT1A1*60 was 20.42 times compared with that in wild-type AA carriers (95%CI: 3.52-118.33). In addition, UGT1A1*28 genetic polymorphism was an independent factor of the occurrence of grade 3-4 neutropenia. The patients with homozygous TA7/7 carriers of UGT1A1*28 had an 1.61 times higher risk of grade 3-4 neutropenia compared with those with wild-type TA6/6 carriers (95%CI: 1.44-12.65). There was no correlation between UGT1A1*93 genetic polymorphism and severe adverse reactions caused by irinotecan. Conclusion: The cancer patients who carried UGT1A1*6, UGT1A1*28 and UGT1A1*60 gene polymorphisms have high risk of severe adverse events caused by irinotecan-based chemotherapy.

Potassium Iodide-Promoted One-Pot Synthesis of Fluoroalkylated Quinoxalines via a Tandem Michael Addition/Azidation/Cycloamination Approach

Fluoroalkylated quinoxlines with various groups were efficiently synthesized via a one-pot tandem Michael addition/azidation/cycloamination process. Under the mild and metal-free conditions, a bis-imine intermediate (4a) was detected and isolated for the first time. KI played a crucial role in this reaction. The mechanism was described.

[3+2] Cycloaddition of N-Aminopyridines and Perfluoroalkynylphosphonates: Facile Synthesis of Perfluoroalkylated Pyrazolo[1,5-a]pyridines Containing a Phosphonate Moiety

1,3-Zwitterions generated from N-aminopyridines in the presence of base are trapped by perfluoroalkynylphosphonates to yield a variety of perfluoroalkylated pyrazolo[1,5-a]pyridine derivatives bearing a phosphonate group. The salient features of these [3+2] cycloadditions include operational simplicity, good tolerance of functional groups, and good to excellent yields at room temperature.

Isocyanide-Based MCRs: Straightforward Access to Perfluroalkyl­ated γ-Spiroiminolactones

A variety of perfluoroalkyl-substituted γ-spiroiminolactones have been synthesized via a one-pot, three-component cascade reaction in which isocyanides, methyl perfluoroalk-2-ynoates and 1,2-diketones undergo highly regioselective Michael addition, nucleophilic addition and cyclization. This reaction has the advantages of good to excellent chemical yields, operationally simple procedure, and short reaction times.

Islet Amyloid Polypeptide Promotes Amyloid-Beta Aggregation by Binding-Induced Helix-Unfolding of the Amyloidogenic Core

Amyloid aggregation of amyloid-beta (Aβ) and islet amyloid polypeptide (IAPP) is associated with Alzheimer's disease (AD) and type-2 diabetes (T2D), respectively. With T2D being the risk factor for AD and the ability of IAPP to cross the blood-brain barrier, the coaggregation of Aβ and IAPP has been explored to understand the cross-talk between the two diseases. Recent studies demonstrated that soluble IAPP could significantly accelerate the aggregation of Aβ while preformed amyloids of IAPP were poor "seeds" for Aβ aggregation. Here, we apply all-atom discrete molecular dynamics simulations to investigate possible molecular mechanisms for the accelerated coaggregation of IAPP and Aβ42 comparing to Aβ42 aggregation alone, which was confirmed by the complementary thioflavin-T fluorescence assay. Our simulation results suggest that peptides in the mixture tend to form heterodimers as the first step toward their coaggregation. Strong interpeptide interactions with IAPP in the heterodimer shift the helical conformation of Aβ42 in its amyloidogenic central hydrophobic core, residues 16-22 (Aβ16-22), to the extended conformation ready to form β-sheets. Our study suggests that the unfolding of Aβ16-22 helix contributes to the aggregation free-energy barrier and corresponds to the rate-limiting conformational change for Aβ42 aggregation. Therefore, we propose that soluble IAPP promotes the aggregation of Aβ42 by binding-induced conformational change of Aβ42 in its amyloidogenic core and thus reduced aggregation free-energy barrier.

Effect of selenium supplementation on pigeon reproductive performance, selenium concentration and antioxidant status

The effects of dietary supplementation of sodium selenite (SS) on the reproductive performance and the concentration of selenium, glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and malondialdehyde (MDA) were determined, and expression of glutathione peroxidase 4 (GPx4) and bone morphogenic protein 15 (BMP15) was evaluated. Paired pigeons (n = 864) were fed: T1 received no SS, while T2, T3, and T4 received 0.5, 1.0, and 1.5 mg of SS/kg of dry matter (DM), respectively. Treatments were performed in triplicate with 72 pairs in each replicate. The results showed that selenium supplementation significantly affected pigeon reproductive performance. Birds fed 1.0 mg of SS/kg displayed higher egg production (P > 0.05), higher birth rate, and lower dead sperm rate than the control group (P < 0.05). Selenium and biochemical analyses revealed a higher selenium concentration in the 1.5 mg of SS/kg group than in the control group (P < 0.05), while GSH-Px was higher in the 0.5 mg of SS/kg group than in the control group (P < 0.05). Neither the MDA nor the SOD content were affected significantly in liver, chest muscle, or leg muscle (P > 0.05); however, in plasma, MDA was lower in the control group (P < 0.05), while SOD was higher in the control group (P < 0.05). qRT-PCR results revealed up-regulation of GPx4 in hypothalamus, pituitary and testis tissues in supplemented groups (P < 0.05). However, expression in ovary differed; GPx4 mRNA levels were lower in the 1.5 mg of SS/kg and control groups than in the 1.0 or 0.5 mg of SS/kg groups (P < 0.05). Expression of BMP15 in the hypothalamus, pituitary, and testis tissues was unaffected (P > 0.05), while in ovary, BMP15 was down-regulated in the 1.5 mg of SS/kg group (P < 0.05). These results suggest pigeons supplemented with SS up-regulated GPx4, 1.0 mg of SS/kg exhibited superior reproductive performance, while 1.5 mg of SS/kg increased the selenium concentration, and 0.5 mg of SS/kg up-regulated GSH-Px activity.

First detection of foot-and-mouth disease virus O/ME-SA/Ind2001 in China

Foot-and-mouth disease (FMD) is endemic in China and is predominantly due to foot-and-mouth disease virus (FMDV) serotype O Mya-98 lineage. In recent years, FMDV O/ME-SA/Ind2001 lineage has spread from the Indian subcontinent to South-East Asia, Middle East and Africa, which may pose potential threats for future trans-regional livestock movements. In this study, we identified the appearance of FMDV O/ME-SA/Ind2001 in China; the first time that this virus lineage has been found there. Sequencing and phylogenetic analysis of VP1 sequences revealed that this newly determined strain belongs to O/ME-SA/Ind2001 sublineage d and is closely related to strains that have caused recent outbreaks of FMD in Nepal, Myanmar, Russia and South Korea. The results suggest extensive movements of the current O/ME-SA/Ind2001 sublineage d viruses and provide essential information for an effective national FMDV control programme in China.

Role of ultrafast dissociation in the fragmentation of chlorinated methanes

Photon-induced fragmentation of a full set of chlorinated methanes (CH₃Cl, CH₂Cl₂, CHCl₃, CCl₄) has been investigated both experimentally and computationally. Using synchrotron radiation and electron-ion coincidence measurements, the dissociation processes were studied after chlorine 2p electron excitation. Experimental evidence for CH₃Cl and CH₂Cl₂ contains unique features suggesting that fast dissociation processes take place. By contrast, CHCl₃ and CCl₄ molecules do not contain the same features, hinting that they experience alternative mechanisms for dissociation and charge migration. Computational work indicates differing rates of charge movement after the core-excitation, which can be used to explain the differences observed experimentally.

[Expression level and clinical significance of LncRNA HOXA11-AS in esophageal squamous cell carcinoma patients]

Objective: To explore the expression of long noncoding RNA (lncRNA) HOXA11-AS in esophageal squamous cell carcinoma tissues and the relationship of HOXA11-AS level with clinical outcomes. Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was applied to detect the expression level of HOXA11-AS in cell lines HET-1A, EC9706, EC109, and in tumor tissue and paired adjacent tissue samples from 73 ESCC patients who received surgical resection.The correlations of the expression level of HOXA11-AS with clinicopathological features and prognosis were also analyzed. Results: The relative expression levels of HOXA11-AS in tumor tissue and paired adjacent tissue were 0.832±0.387 and 2.486±1.087, respectively, with significant difference (P<0.001). The expression of HOXA11-AS was upregulated in 63.0%(46/73)ESCC tissues. The relative expression levels of HOXA11-AS in HET-1A, EC-9706 and EC-109 cells were 1.000, 23.553±3.221 and 17.217±1.968, respectively. The expression level of HOXA11-AS was upregulated in ESCC cell lines (P<0.001). High expression level of HOXA11-AS was correlated with histological grade and lymph node metastasis of ESCC patients (P<0.05). However, it was not associated with the age, gender, depth of infiltration and TNM staging (P>0.05). The median overall survival (OS) and median disease-free survival (DFS) of patients with low HOXA11-AS expression were 43 months and 42 months, respectively, significantly longer than 37 months and 28 months of patients with HOXA11-AS high expression (P<0.05). Cox model multivariate analysis showed that the expression of HOXA11-AS and lymph node metastasis were independent factors of poor prognosis of ESCC patients. Conclusions: The expression of HOXA11-AS is upregulated in esophageal cancer cell lines and tissues. High expression of HOXA11-AS is associated with poor prognosis of ESCC patients.Therefore, LncRNA HOXA11-AS may serve as a predictive marker of postoperative ESCC patients.

Does a mandibular access osteotomy improve survival in pT2 oral tongue cancers? Retrospective study at a single institution

The surgical approach to the resection of oral tongue cancers can involve transoral resection (TOR) or a temporary mandibulotomy access (TMA). There are no relevant guidelines, and the oncological safety of TOR needs consideration. The objective of this study was to investigate TMA and TOR in pT2 oral tongue cancer surgery with regard to cancer outcomes. Demographic, surgical, and histology data from primary pT2 tongue cancers were recorded and evaluated through multivariate Cox regression for local recurrence (LR), disease-free survival (DFS), and overall survival (OS). A total of 166 patients with pT2 primary oral tongue cancer fulfilled the inclusion criteria; TOR was used in 95 patients and TMA in 71 patients. The minimum follow-up was 29 months. Group comparisons showed a significantly higher frequency of perineural spread (P=0.013) in the TMA group; a higher frequency of involved margins on initial resection was seen in TOR patients (P=0.010). Adjuvant postoperative radiotherapy was preferred in the TMA group, in line with the high pN positive status. Multivariate Cox regression showed significantly higher LR and lower DFS in the TOR group despite stratification of the major prognostic factors. The 5-year survival rate was reduced to 82.2% in the TOR group, while it remained constant at 93.0% in the TMA group. TMA provided superior local control and DFS compared to TOR in pT2 tongue cancers.

Suspended silicon waveguides for long-wave infrared wavelengths

In this Letter, we report suspended silicon waveguides operating at a wavelength of 7.67 μm with a propagation loss of 3.1±0.3  dB/cm. To our knowledge, this is the first demonstration of low-loss silicon waveguides at such a long wavelength, with loss comparable to other platforms that use more exotic materials. The suspended Si waveguide core is supported by a sub-wavelength grating that provides lateral optical confinement while also allowing access to the buried oxide layer so that it can be wet etched using hydrofluoric acid. We also demonstrate low-loss waveguide bends and s-bends.

Primary intraosseous squamous cell carcinoma of the mandible: locoregional control and survival is significantly reduced if the tumour is more than 4cm in size

To establish the prognostic factors for primary intraosseous squamous cell carcinoma we designed a retrospective study of patients treated in the head and neck department of a tertiary referral centre in China from 2010-2015. We collected clinical, radiological, and histopathological data from 36 patients treated during the given time period, among which 34 were followed up. There were 22 male and 12 female patients, 13 of whom gave a history of smoking tobacco and four who drank alcohol. All 34 patients were treated by segmental mandibulectomy and neck dissection. Nine had cervical lymph node metastases on histopathological examination, and none had invaded surgical margins. Twenty-eight were treated with radiotherapy postoperatively. During follow up nine died of locoregional recurrence or metastases. Specific factors such as cervical lymph node metastases were related to a greater likelihood of locoregional recurrence. Patients who drank alcohol were also more likely to develop metastases postoperatively. Tumours more than 4cm in size were significantly associated with reductions in locoregional control and survival.

Hemodynamic Changes Caused by Multiple Stenting in Vertebral Artery Fusiform Aneurysms: A Patient-Specific Computational Fluid Dynamics Study

BACKGROUND AND PURPOSE

The multiple stent placement technique has largely improved the long-term outcomes of intracranial fusiform aneurysms, but the hemodynamic mechanisms remain unclear. In this study, we analyzed the hemodynamic changes caused by different stent-placement strategies in patient-specific models using the computational fluid dynamics technique, aiming to provide evidence for clinical decision-making.

MATERIALS AND METHODS

Ten vertebral artery fusiform aneurysms were included, and their patient-specific computational fluid dynamics models were reconstructed. A fast virtual stent placement technique was used to simulate sequential multiple stent placements (from a single stent to triple stents) in the vertebral artery fusiform aneurysm models. Hemodynamic parameters, including wall shear stress, pressure, oscillatory shear index, relative residence time, and flow pattern, were calculated and compared among groups with different numbers of stents.

RESULTS

Virtual stents were deployed in all 10 cases successfully, consistent with the real stent configuration. Wall shear stress decreased progressively by 7.2%, 20.6%, and 25.8% as the number of stents increased. Meanwhile, relative residence time and pressure increased on average by 11.3%, 15.4%, and 45.0% and by 15.7%, 21.5%, and 28.2%. The oscillatory shear index showed no stable variation trend. Flow patterns improved by weakening the intensity of the vortices and displacing the vortex center from the aneurysmal wall.

CONCLUSIONS

Stent placement modifies hemodynamic patterns in vertebral artery fusiform aneurysms, which might favor thrombosis formation in the aneurysmal sac. This effect is amplified with the number of stents deployed. However, a potential risk of rupture or recanalization exists and should be considered when planning to use the multiple stent placement technique in vertebral artery fusiform aneurysms.

An unconventional family 1 uracil DNA glycosylase in Nitratifractor salsuginis

The uracil DNA glycosylase superfamily consists of at least six families with a diverse specificity toward DNA base damage. Family 1 uracil N-glycosylase (UNG) exhibits exclusive specificity on uracil-containing DNA. Here, we report a family 1 UNG homolog from Nitratifractor salsuginis with distinct biochemical features that differentiate it from conventional family 1 UNGs. Globally, the crystal structure of N. salsuginisUNG shows a few additional secondary structural elements. Biochemical and enzyme kinetic analysis, coupled with structural determination, molecular modeling, and molecular dynamics simulations, shows that N. salsuginisUNG contains a salt bridge network that plays an important role in DNA backbone interactions. Disruption of the amino acid residues involved in the salt bridges greatly impedes the enzymatic activity. A tyrosine residue in motif 1 (GQDPY) is one of the distinct sequence features setting family 1 UNG apart from other families. The crystal structure of Y81G mutant indicates that several subtle changes may account for its inactivity. Unlike the conventional family 1 UNG enzymes, N. salsuginisUNG is not inhibited by Ugi, a potent inhibitor specific for family 1 UNG. This study underscores the diversity of paths that a uracil DNA glycosylase may take to acquire its unique structural and biochemical properties during evolution.

DATABASE

Structure data are available in the PDB under accession numbers 5X3G and 5X3H.